nixos/3proxy: fix documentation link formatting

Changed files
+1 -1
nixos
modules
services
networking
+1 -1
nixos/modules/services/networking/3proxy.nix
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test2:CR:$1$rkpibm5J$Aq1.9VtYAn0JrqZ8M.1ME.
```
-
You can generate md5-crypted passwords via https://unix4lyfe.org/crypt/
+
You can generate md5-crypted passwords via <https://unix4lyfe.org/crypt/>
Note that htpasswd tool generates incompatible md5-crypted passwords.
Consult [documentation](https://github.com/z3APA3A/3proxy/wiki/How-To-%28incomplete%29#USERS) for more information.
'';